It is general knowledge that the individual detector elements which are contained in the detector modules of a computed tomograph and supply the detector module's channels with signals have temperature-dependent signal errors which are corrected using correction tables stored in the computed tomograph's processor. Such a correction table uses the differential changes in a detector's channel signals for a respectively prescribed configuration of the detector modules in the detector.
Creating this correction table requires a high level of involvement. Further, it is created in the factory upon the delivery of a computed tomograph for the detector with its detector modules in the respective configuration which is to be delivered. If a detector module, or usually one or more channels in a detector module, is faulty, it is necessary to exchange this module.
Since each detector module has correction values which are firstly module-typical but are secondly also dependent on the respective module configuration, that is to say on a detector module additionally provided in the detector, it is not simply possible to create such a correction table for each individual detector module away from its surroundings. Instead, it is necessary to create the correction table for the new detector module in relation to the surroundings of the entire detector, more precisely in relation to the surroundings of the other detector modules in the overall detector, that is to say in the respective module configuration.
This currently indicates that exchanging a detector module requires highly qualified personnel with correspondingly complex testing equipment to create such a correction table at the site of the computed tomograph, that is to say generally on the customer's premises. Such a method is complex, time-consuming and correspondingly expensive, particularly “in situ”.